A gimbal platform is a supporting worktable for mounting a camera. A lens of the camera can be adjusted by adjusting the gimbal platform to take a photo or video of a target. In existing common hand-held gimbal platforms, a roll axis arm and a motor are usually designed and manufactured separately. The roll axis arm can include a left arm, a transverse arm, and a right arm, which can be fixed by screws and then assembled with the motor. The existing gimbal platforms have the following disadvantages: 1. the amount of parts is large, and the assembly is complicated, which is disadvantageous for cost control; 2. multiple parts are fitted with each other, which requires high processing precision of the fitting faces; and 3. coaxiality of the bearing holes of the left and the right arms after assembly cannot be ensured in mass production.